// run: $exec < input
#include <cstdio>

int const maxn = 210000;
long long a[maxn];
int n, k;

int main()
{
	std::scanf("%d %d", &n, &k);
	for (int i = 1; i <= n; i++) std::scanf("%I64d", &a[i]);

	long long sum = 0, now = 2, tot = n;
	for (int i = 2; i <= n; i++) {
		long long tmp = sum - (now - 1) * (tot - now) * a[i];
		if (tmp < k) {
			std::printf("%d\n", i);
			tot--;
		} else
			sum += (now++ - 1) * a[i];
	}
}

